Oil futures rose Monday as violence in Libya renewed concerns the nation’s oil output would stay below full capacity, keeping global oil supplies tight.  Light, sweet crude for June delivery rose 79 cents, or 0.8%, to $102.81 a barrel on the New York Mercantile Exchange. Brent crude on ICE Futures Europe rose 40 cents, or 0.4%, to $110.15 a barrel.

Fighting broke out in Libya over the weekend, and a military police chief claimed to have disbanded the General National Congress, a claim that was denied by the state-run Libyan News Agency, Bloomberg News reported.

Libya’s oil production has fallen from 300,000 barrels a day last week to 200,000 barrels a day, according to Commerzbank. The nation has a production capacity of about 1.5 million barrels a day.

“In light of the latest reports, any significant and lasting rise in the production level appears illusory,” Commerzbank wrote.

The government reached an agreement with rebels in recent weeks to reopen some export terminals that had been blockaded in eastern Libya, but the stability of those agreements is in question.

“Any potential power struggle at the oil terminals again could see (production) reduced to zero,” said Matt Smith, commodity analyst at Schneider Electric SA (SU.FR), an energy-consulting firm.

The renewed supply concerns were bolstered by the International Energy Agency’s report last week, which projected a tighter supply-and-demand outlook for the second half of the year. The agency called for the Organization of the Petroleum Exporting Countries to boost its output in the second half of 2014 to meet demand amid supply outages.

Prices also gained support from the ongoing unrest in Ukraine, which some worry could lead to further sanctions that would crimp Russia’s oil exports. Russia is the No. 2 oil-exporting nation after Saudi Arabia.

U.S. and European Union sanctions have so far not affected Russia’s energy output. But Western officials have threatened to apply more sanctions if Russia disrupts Ukraine’s national election May 25. German’s economy minister reiterated this threat Sunday.

Front-month June reformulated gasoline blendstock, or RBOB, recently rose 1.56 cents, or 0.5%, to $2.9891 a gallon. June diesel rose 1.70 cents, or 0.6%, to $2.9706 a gallon.

By Nicole Friedman